One known cheek plate adjusting device for a stuffer box crimper is fixed by screw 17 on base frame 14. It is widely practiced that two cheek plates 13 are installed on two sides of a pair of nip rollers 15 and a preset clamping force is maintained between cheek plates 13 and the sides of the pair of nip rollers 15. The clamping force is adjusted to such a preset value that it prevents materials from being squeezed out of the edges of the pair of nip rollers while minimizing the friction force between the cheek plates 13 and the pair of nip rollers 15. The clamping force value is adjusted by turning or adjusting screws 16 in or out to move wedge blocks 12 relative to brackets 11, which pushes the cheek plate 13 against the sides of the pair of nip rollers 15. However, it is difficult to adjust the clamping force precisely to the preset value. During operation of the crimper, grinding friction between the surfaces of the static cheek plates and the sides of the fast rotating nip rollers will lead to mechanical wear of the surfaces of the cheek plate, or the sides of the nip rollers, or both, which, after a long period operation, can produce gaps between the cheek plates 13 and the sides of the nip rollers 15. The materials may be squeezed into the gaps, causing damage to the materials and thus affecting product quality. This mechanical wear is a continuous process and the gap becomes bigger gradually, which makes it necessary to make periodic manual adjustment because the current device lacks automatic adjustment mechanism. One patent, No. ZL200320110083.7, related to the present field of invention, disclosed a design that changed the shape of the surface of the wedge that is in contact with the bracket from flat to cylindrical, which solved the problem of parallel adjustment between the cheek plates and the side surfaces of the pair of nip rollers and enables more complete contact between the cheek plates and the side surfaces of the pair of nip rollers.